The invention relates to a laser cutting device, in particular to a high precision laser cutting machine for PCB boards, which comprises a feed and discharging mechanism, a working platform, a laser cutting device, a feed slipway, a discharging slipway, a feed positioning and clamping device, a feed platform and a discharging platform, wherein the feed slipway and the discharging slipway are arranged on the horizontally movable feed and discharging mechanism, linked with the feed and discharging mechanism, and are respectively provided with a feed device and a discharging device which can be move up and down relative to the feed slipway and the discharging slipway the lower part of the feed device is provided with the feed platform the lower part of the discharging device is provided with the discharging platform the feed positioning and clamping device arranged on the working platform is arranged between the feed platform and the discharging platform, and can reciprocate along the horizontal direction and the back and forth direction relative to the working platform and the laser cutting device is positioned above the feed positioning and clamping device. The laser cutting device has high automation degree, high processing precision, automatic positioning of material sheets with convenience and accuracy, simple operation and convenient cutting.